Improvement in hot-air furnaces



UNITED STATES PATENT. OFFICE.

PETER MARTIN, OF CINCINNATI, OHIO.

IMPROVEMENT lN HOT-AIR FURNACES.v

Specification forming part 'of Letters Patent N0. l 10,664, daicd Jflllufll'y 3, 137,1-

To (LZZ whom may con/cern,.- Be it known that I, PETER MARTIN, of Cincinnati, Hamilton county, Ohio, have invented certain Improvements in Varm-A'ir Furnaces; of which the following is a specification.

This invention relates to that class of apparatus which is employed for warming churches,l schools, dwelling-houses, Src.; and my present improvement consists in arranging the pipes which carry oft` the products of combustion in Y such a manner as to effectually consume the smoke, thereby overcoming one of the principal objections to such furnaces, and causing' them to give out a large amount of heat with the least consumption of fuel.

In the accompanying drawings, Figure l is a vertical section of my improved furnace, the section being taken at the line X X. Fig. 2

.is another vertical section of the same at the and ash-pit, and said diaphragm is furnished Awith a central opening, e, having a lid, e', the

removal of which allows soot, ashes, and. other obstructions to. be withdrawn from chamber A.

Situated near the upper end of ash-pit B, and supported upon feet or lugs F, is a ring, G, to which is pivoted,at h h', the two semicircular drop-grates, H H', that are retainedin their normal or horizontal positions by the cranked portion I of rock-shaft I. This rock-shaft, after being passed through the neck?) of pit B, is journaledin hangers g, which depend from the ring G, and the external end of said rock-shaft is provided with a non-circular head, fi, for the reception of a spanner or wrench, by which it may be rotated whenever occasion requires. By apartial rotation of said shaft the grates will be agitated sufficiently to rattle out the ashes, and by a complete revolution of said shaft, so as to bring its cranked portion I to the position shown by dotted lines in Fig. 1, the entire contents of the fire-chamber will be dumped into the ashpit B. l

Resting upon the ring G, and in line with mar ginal recesses g of the same, are aseries of semi-cylindrical tubes, J ,-which, in connection with the inner portion of the chamber C, form channels K, up which the' smoke, gas, dre., ascend after they have entered said channels through the perforations j in the lower portions of tubes J. The channels K communicate at their upper ends `with the external side pipes, D, and the smokev and gas from the iire, after ascending said channels, descend through said side pipes and mix in the combustionchamber A, from which they escape through the large flue L and pipe M. rlhis flue L' is formed by a portion of the interior walls of the pit B and chamber O, and an imperforate curved plate or semi-tube, N, which latter is located entirely within chambers B C, and at the rear side of the same. The curved and imperferate plate N commences at the diaphragm E,

and, after passing through a recess, g, in the ring G, extends up almost to the top of vchamber C, and the upperportion of said plate has an opening, n,which is closed bya damper, O. This plate, being situated within the furnace, becomes very highly heated, and as the products of combustion from chamber A are compelled to traverse the entire length of flue L before escaping from pipe M, they are thus brought into intimate contact with the heated plate N, and the smoke is thereby effectually consumed, nothing but an invisible gas or vapor escaping through pipe M. When re is first kindled in the furnace, the damper O is opened, as shown by dotted lines in Fig. 2, so as to allow the smoke to escape directly into the pipe M; but after the `iire has got well under way said damper is closed, and the products of combustion are compelled to take the above-described circuitous route before escaping from the apparatus. The tubes J and N are tted within lugs P, which project from the interior of the furnace, and their upper ends are covered with caps R. The chambers A B C, together with their side pipes D, are all incased Within a shell, S,which may be-of masonry, corrugated iron, or any other suitable material, and said shell is closed at top by a plate, T, having necks t, to which pipes are to be attached for conducting warm I4 air to the various rooms of the house in which the furnace is situated. The shell S has open'- ings s at its bottom, through which cold air enters.

Q and Uare passages leading to the ash-pit and iire-chamber, respectively, and said passages are closed with doors V and W, the former of which has a register, o, for regulating the quantityof air flowing into the ire. If preferred, the fire-chamber C may be cast with corrugations o, as shown in Fig. 3, and I said corrugations can be so arranged as to constitute part of the iiues K and L, for the purpose of increasing the area of the same.

The corrugations c, instead of being located only where the ilues occur, may be su'ficiently `nnnierous to entirely surround the line-chainber.

The interiorof olianiberC maybe lined with fire-tiles.

The smoke-pipe M may be omitted, and the flue L carried np through the top plate, T.

I claim as my invention" l. The combination, substantially as described, of the combustionchamber A, ash pit B, nre-chamber C, external side pipes, D, diaphragm E, interior and perforated tubes, .I j, channels K, flue L, and internal and i1nperforatey plate N, for the object stated.

2. In combination With the tubes J or N, the corrugations c of the fire-cl1an1ber C, for the purpose herein set forth.

3. In combination with the parts A, B, C,

D, E, K, L, and M, the opening n and damper O, for the object described.

In testimony of which invention Ihave here unto set my hand.

PETER MARTIN.

Vitnesses:

G-Eo. II. KNIGHT, XVM. F. BAUER. 

